## Pages

### KenKen - fun puzzle arithmetic practice

Ken means Wisdom in Japanese, but the original name for this puzzle was,

"The Kashikoku Naru Puzzle"

which means

"The It Makes you Smarter Puzzle"
(source

I first heard of these puzzles when my dad brought these KenKen books out from the UK for our girls. KenKen are a kind of sudoku type puzzle that works on arithmetic and logic. They were invented by a Japanese maths teacher as a way to train young brains in arithmetic in a fun puzzle type manner. In the foreword to each book, the creator, Tetsuya Miyamoto says,

"It's important that the learning process is enjoyable. KenKen is ideal for making the learning process enjoyable and is perfect for all ages."

How to play

The logic part
Each puzzle has a grid, and like in sudoku and each square in the grid contains a number. If the grid has 3 squares across then those numbers will be 1,2 and 3. If it has 4 squares the numbers will be 1,2,3 and 4; and so on. No number can be repeated in any column or any row.

Now for the arithmetic part
The small numbers found at the top left corner of a square is the answer to the particular maths function of the numbers in that block. The top of the puzzle will tell you if you are adding, subtracting, multiplying or dividing.

Here's an example of a small multiplication puzzle. In the top right of the page you see a 'x' sign telling you this is a multiplication puzzle.
If you look at the top left corner of each block - this tells you the answer of the numbers in that block multiplied together. So in the top left block there is a 2 which tells us the two numbers in that block must be 1 and 2,  the order of those numbers must then be determined.
If we look at the block on the left below, the number 3 tells us the two numbers in that block must be 1 and 3, so the number in the top left must then be 2, so that the left column has all three numbers present. In the centre of the square that block has a 2, so that one is simple - place a 2 in that box!

The puzzle is worked out using each block in turn.

Here's an example of another puzzle:
You can see at the top right of this page there is a '+'  and a"-" symbol, telling us it's an addition and subtraction puzzle. There are 5 squares across so each row and column must contain the numbers 1,2,3,4 and 5.
The top left block has 2 numbers that added together make 9. Of the numbers we can use, these must be 4 and 5.  Then again the order must be determined.
Each block must be worked through to work out the numbers and positions,

Fun and educational
These puzzles really are fun to do. They help practice basic arithmetic skills, develop concentration, perseverance and logical thinking, and there are varying levels for all abilities.

You can find KenKen in newspapers, magazines, books and also online and in downloadable apps.
The official KenKen website has daily puzzles, customizable puzzles and free weekly printable email puzzles for teachers to use in classrooms.

Mr Miyamoto developed these puzzles based on his philosophy of 'Teaching without teaching".

Kids will far prefer doing puzzles and games to maths problems and worksheets - but if you find the right puzzles and games they teach the same things!

Have you or your kids ever tried KenKen?

I would definitely recommend giving them a try!